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SpaceX Landing Attempt Video Released

kellymcdonald78 Re:Wait a minute (248 comments)

Stage separation on Falcon is not hydraulic (it's electro mechanical), however you are correct there has been no details released on if the grid fins have a separate system or not.

about a week ago
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SpaceX Landing Attempt Video Released

kellymcdonald78 Re:Wait a minute (248 comments)

Falcon uses RP-1 as hydraulic fluid so it is likely burned as fuel

about two weeks ago
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Parents Investigated For Neglect For Letting Kids Walk Home Alone

kellymcdonald78 Re:A horror story (779 comments)

I know its horrible. I stopped driving with my kids after a child in my city was killed in a car accident. Then I read that some kids were killed by a gunman at a school and decided to pull them out. Sports was next when I heard that some kid was hit in the chest by a soccer ball and died from cardiac arrest. I am currently thinking about covering my kids with bubble wrap and locking them in their rooms, but then again there was a house fire last week and I saw that someone choked on bubble wrap. I'm not sure what approach I should take to guarantee my children a 100% risk free life. You do realize, that by every measure "Modern Society" is safer for children (and adults) than at any other time in human history. A child has a greater chance of being struck by lightning than being kidnapped. We're creating a whole generation of children that are so fragile, they will crumple at the first sign of adversity.

about two weeks ago
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Why We Have To Kiss Off Big Carbon Now

kellymcdonald78 Re:The pendulum swings too far... (441 comments)

At which point the power grid will collapse as we add an additional 30% load onto the system

about two weeks ago
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Why We Have To Kiss Off Big Carbon Now

kellymcdonald78 Re:The pendulum swings too far... (441 comments)

Even if the sale of non-electric cars were banned tomorrow. Half the vehicles on the road would still be gas powered in 2026 (average age of a vehicle in the US is 11 years). As much as I am rooting for Tesla, to think that even a moderate proportion of vehicles will be electric 20 years from now is ludicrous. 0.6% of vehicles sold in the US are electric or plug in hybrid, even if this gets to 10%, or 20% in a decade, the majority of vehicles will be gas powered well into the 2040's. Low gas prices makes this even harder to achieve as it impacts the economics of buying an EV. Low prices also impact the movement to more efficiency and investment in alternatives. when fuel is cheap, people wont invest to "drop demand by 40%" because it isn't economically rational. People fail to realize just how dependent the modern world is on fossil fuels. Fully 80% of the energy mankind consumes comes from fossil fuels. Nuclear, hydro, biomass, wind, solar, everything else is only 20%. The amount of infrastructure we would have to replace to make solar and wind anything more than a blip on the radar is measured in the $trillions

about two weeks ago
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Chinese Spacecraft Enters Orbit Around the Moon

kellymcdonald78 Re: Success rate of 0% (152 comments)

Agree on the QA issues, but that reflects on lack of funding and resources. Even then, only 1 of the 4 N-1 launches failed due to QA (The second flight when an engine ingested a loose bolt). The rest were all design issues (Flight 1: high frequency oscillations, Flight 3: insufficient control authority, Flight: 4 pogo). Bear in mind that these were all issues with the first stage, the upper stages were NEVER tested (engines yes, but not stages). Without test stands to validate and debug the design before first flight there was no guarantee that assuming they had finally resolved the first stage issues, that there wouldn't have been a slew of other problems with the 3 upper stages. .

about two weeks ago
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Chinese Spacecraft Enters Orbit Around the Moon

kellymcdonald78 Re:Success rate of 0% (152 comments)

In my view the problems facing the Soviet space program at the time were just too systemic for even Korolev to have resolved. Unlike the US which had NASA and thus a single coordinated moon program, the Soviets essentially had 3. Korolev, Yangel and Chelomei were constantly fighting each other for political influence and funding. Even then, the funding never matched the grandiose political statements (similar to NASA today). While Sputnik, Vostok and Voshod could be accomplished on a shoestring budget, leveraging the R-7 program, the Soyuz, N1 and LK (the Soviet Lunar Lander) programs required substantial investment that never really emerged. Korolev was never able to build a test stand for the N-1 due to lack of funding, meaning they had to "debug" it in flight, an insane approach for something as large, complex (and expensive) as the N-1. In 1966, Korolev spent the entire annual N-1 budget by March and wasn't able to do anything more until the next year. The under investment in Soyuz resulted in Komarov's death on a spacecraft no where near ready to carry a crew. The first unmanned flight of the LK didn't even take place until the end of 1970. It's interesting to note that the slashing of NASA's budget began in 1967, shortly after the CIA released its intelligence estimate on the state of the Soviet Space Program. While they indicated a manned flyby by 1968 was likely, a manned landing wasn't likely until 1972 if at all.

about two weeks ago
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Chinese Spacecraft Enters Orbit Around the Moon

kellymcdonald78 Re:Success rate of 0% (152 comments)

No, the Russian's were hoping to do a manned flyby as part of the Zond program, but the Proton rocket had a number of teething problems and it took awhile to become reliable enough to even consider putting people on (ultimately it never flew manned). There were also a number of problems with the Soyuz 7K-L1 spacecraft. US intelligence thought the Soviet's were closer to flying a crewed lunar flyby mission as Zond 5 was largely a successful test. However Zond 6 depressurized and crashed on re-entry (killing the animals aboard) which ended any immediate plans of a crewed launch. Apollo 8 was originally to be a "D" mission, testing the Lunar Module in Low Earth Orbit with Apollo 9 an "E" mission testing it in Medium Earth Orbit. Due to delays with the Lunar Module, they decided to swap the missions and instead send Apollo 8 into lunar orbit (with no Lunar Module). Frank Borman, Jim Lovell, and Bill Anders became the first humans to leave low Earth orbit Dec 21st, 1968. They successfully orbited the moon 10 times on Christmas day and returned Dec 27th After that the Soviet's pretty much gave up on the flyby in favor of a manned lunar landing, but they could never get the N-1 rocket to work

about two weeks ago
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Sir Richard Branson Quietly Shelves Virgin Submarine Plan

kellymcdonald78 Re:No so easy as throwing money at it, is it? (47 comments)

Actually the cost of Apollo is dwarfed by the F-35 program. Apollo was about $110 Billion in current dollars (about the same price as ISS), the F-35 program is $1.5 trillion.

about a month and a half ago
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Fusion and Fission/LFTR: Let's Do Both, Smartly

kellymcdonald78 Re:Fission is Dead (218 comments)

Firstly, naval reactors run on highly enriched Uranium (90+% U-235), which is incredibly expensive and represents significant proliferation risk (you wouldn't want to give Homer Simpson access to "bomb grade" uranium) Secondly, you may also want to look up who built the reactors for the Enterprise, Nautilus, Nimitz class, about half the sub fleet and operated the Bettis Atomic Power Laboratory from 1949 to 2008 (Hint the company name starts with a 'W')

about 3 months ago
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Air Force To Take Over Two Ex-Shuttle Hangers In Florida For Its X-37B Program

kellymcdonald78 Re: Why aren't we using these space shuttles? (48 comments)

The propulsion system uses hydrazine, Rudy. We wanna breathe, not dry clean our lungs.

about 4 months ago
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Lego Ends Shell Partnership Under Greenpeace Pressure

kellymcdonald78 President Business agrees (252 comments)

Just means Octan has an energy monopoly for all those LEGO cars, trucks and planes now

about 4 months ago
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NASA Asks Boeing, SpaceX To Stop Work On Next-Gen Space Taxi

kellymcdonald78 Re: Maybe affects Boeing, not SpaceX (139 comments)

SpaceX has been profitable since 2010, not sure where you're getting your information from.

about 4 months ago
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Solar Powered Technology Enhances Oil Recovery

kellymcdonald78 Re:Renewable (82 comments)

Before the massive glut in tight gas due to fracking, there were serious plans to build a nuclear reactor in Northern Alberta for exactly that purpose (steam for in-situ oil sands extraction). However now that the price of natural gas has cratered in North America, its much more cost effective to use it for steam

about 4 months ago
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Congress Can't Make Asteroid Mining Legal (But It's Trying, Anyway)

kellymcdonald78 Re: Precident has been set (213 comments)

Read article 16 of the treaty. All anyone has to do it give 1 year notice to withdraw

about 4 months ago
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Reno Selected For Tesla Motors Battery Factory

kellymcdonald78 Re:That's not what MotherJones says (157 comments)

It's possible to generate 25% margin on each car, yet still have the company post a loss (Learn to read an Income Statement). All it requires is the company to re-invest all of that margin (and more) say... building a Gigafactory or other R&D or expansion activities. When you're in a growth phase like Tesla and your overriding objective is to scale the business, you would expect the company to be running on the edge of profitability, simply because every dollar in profit is a dollar that can be used to fund your expansion.

about 5 months ago
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Battle of the Heavy Lift Rockets

kellymcdonald78 Re: Why does it take so long? (211 comments)

While the "Shuttle Derived" messaging was used to sell the program, it's hardly anything but. The first few flights will use left over RS-25Ds from the shuttle program, but they are far too expensive for new ones to be built and throw away each flight, so the RS-25E and RS-25F engines needed to be developed. The 4 segment SRBs from the shuttle aren't powerful enough for SLS so they've had to develop a 5 segment SRB with a new type of solid fuel with a completely new grain. The casings are also being redesigned to be expendable. While the tank is shuttle derived, it needs a completely redesigned aft section to support the engines, plumbing is completely different, and the a new interstate to support the upper stage and payloads. It would have been cheaper and faster to start from scratch, but that doesn't keep the trough filled.

about 5 months ago
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Russian Military Forces Have Now Invaded Ukraine

kellymcdonald78 Re:A bit less than 10 years ago (848 comments)

The paper is filled with "potentially", "possibly", "reasonable chance of success", "our model fails to incorporate several factors" etc. As well several of the "counterforce" targets on the list are inconveniently located in or near major population centers (Naval bases for example). For example Polyarny had a population of 30,000 in the early 90's. Murmansk which is only 30km away has a population of 300,000.

about 5 months ago
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Russian Military Forces Have Now Invaded Ukraine

kellymcdonald78 Re:A bit less than 10 years ago (848 comments)

"Mr. President, I'm not saying we wouldn't get our hair mussed. But I do say no more than ten to twenty million killed, tops. Uh, depending on the breaks." Gen Buck Turgidson

about 5 months ago

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